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arXiv · 2203.03084

Preparation of Metrological States in Dipolar-Interacting Spin Systems

Tian-Xing Zheng·Anran Li·Jude Rosen·Sisi Zhou·Martin Koppenhöfer·Ziqi Ma·Frederic T. Chong·Aashish A. Clerk·Liang Jiang·Peter C. Maurer
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Abstract

Spin systems are an attractive candidate for quantum-enhanced metrology. Here we develop a variational method to generate metrological states in small dipolar-interacting ensembles with limited qubit controls and unknown spin locations. The generated states enable sensing beyond the standard quantum limit (SQL) and approaching the Heisenberg limit (HL). Depending on the circuit depth and the level of readout noise, the resulting states resemble Greenberger-Horne-Zeilinger (GHZ) states or Spin Squeezed States (SSS). Sensing beyond the SQL holds in the presence of finite spin polarization and a non-Markovian noise environment.

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Tian-Xing Zheng, Anran Li, Jude Rosen, Sisi Zhou, Martin Koppenhöfer, Ziqi Ma, Frederic T. Chong, Aashish A. Clerk, Liang Jiang, Peter C. Maurer. 2022-03-07. Preparation of Metrological States in Dipolar-Interacting Spin Systems. https://doi.org/10.1038/s41534-022-00667-4

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